President Trump on Thursday again slammed special counsel Robert Mueller’s investigation as a “witch hunt” and claimed that prosecutors gave his former national security adviser, Michael Flynn, “a great deal” because they felt badly about how he had been treated.

“They gave General Flynn a great deal because they were embarrassed by the way he was treated – the FBI said he didn’t lie and they overrode the FBI,”Trump wrote on Twitter. “They want to scare everybody into making up stories that are not true by catching them in the smallest of misstatements. Sad!”

They gave General Flynn a great deal because they were embarrassed by the way he was treated – the FBI said he didn’t lie and they overrode the FBI. They want to scare everybody into making up stories that are not true by catching them in the smallest of misstatements. Sad!……

Flynn, who served a brief stint as Trump’s national security adviser, pleaded guilty to lying about his contacts with the Russian ambassador to the U.S. last December and agreed to cooperate in Mueller’s investigation.

Mueller has described Flynn’s cooperation as valuable. Earlier this week, Flynn asked a federal judge to spare him from prison time and instead sentence him to at most one year probation.

In a memo filed in federal court late Tuesday, Flynn’s defense attorneys also suggested that he had been duped by FBI agents who handled his interview, playing into a theory among conservatives that Flynn had been wrongly led to commit a federal crime.

Mueller has recommended Flynn serve no jail time, citing his “substantial assistance” in the ongoing investigation into Russian interference in the 2016 election. Flynn, who served on the Trump campaign before moving to the White House, is said to have offered the special counsel valuable details about contacts between the campaign and Russia as well as information related to other unknown matters under investigation.

Flynn is scheduled to be sentenced in D.C. federal court on Dec. 18.

Late Wednesday, the judge overseeing his case, U.S. District Judge Emmet G. Sullivan, asked both Flynn and Mueller to turn over additional materials related to Flynn’s January 2017 interview with the FBI in which he later admitted he lied about his Russia contacts.

It is possible but unclear whether the developments could delay Flynn’s sentencing.